Environmentally controlled induction heating system for heat treating metal billets

A system for heating metal billets comprising:

• (a) a heating chamber;
• (b) a cold billet load chamber;
• (c) a loading chamber;
• (d) a transfer chamber;
• (e) a hot billet dump chamber;
• (f) a return chamber;
• (g) means for substantially evacuating air from the cold billet load chamber, loading chamber, heating chamber, transfer chamber and return chamber, said means for substantially evacuating air being fluidly coupled to said heating chamber, cold billet load chamber, loading chamber, transfer chamber and return chamber;
• (h) means for supplying an inert gas into the loading chamber, heating chamber, transfer chamber and return chamber, said means for supplying an inert gas being fluidly coupled to said loading chamber, heating chamber, transfer chamber and return chamber;
• (i) means for maintaining inert gas in the heating chamber, said means comprising a first vacuum gate and a second vacuum gate, said first vacuum gate allowing metal billets to be placed in the cold billet load chamber when said first vacuum gate is open and providing a hermetic seal when said first vacuum gate is closed, and said second vacuum gate maintaining inert gas in the heating chamber when said second vacuum gate is closed;
• (j) means for removing impurities from the inert gas, said means comprising a gettering system, said gettering system being fluidly coupled to said heating chamber;
• (k) a slide rail extending through the heating chamber, a plurality of trolleys slidably disposed on the slide rail, and a plurality of carriers mounted on the plurality of trolleys for transporting the metal billets through the heating chamber, and
• (l) a plurality of induction heating coils disposed inside said heating chamber for heating the billets;
• wherein said cold billet load chamber is disposed between and connected to said loading chamber and said return chamber, said loading chamber is disposed between and connected to said cold billet load chamber and the heating chamber, said heating chamber is disposed between and connected to said loading chamber and said transfer chamber, said hot billet dump chamber is coupled to said heating chamber, said transfer chamber is disposed between and connected to said heating chamber and said return chamber, and said return chamber is disposed between and connected to said cold billet load chamber and said transfer chamber, so as to form a continuous system.